Persons with severe physical disabilities require the use of power wheelchairs for mobility, which are typically controlled through a joystick. However, when the user has no functional control of his/her upper extremities (e.g. quadriplegia) using a joystick becomes inadequate. In these cases the use of alternate control systems is needed such as head arrays, chin joysticks, foot control, etc. Several progressive conditions such as multiple sclerosis (MS) and amio-lateral sclerosis (ALS) often render these alternate systems unusable since voluntary motor control becomes extremely limited. For such severe cases a single switch-driving system (e.g. blink switch, puff switch, EMG switch) is used to control a scanning array linked to the wheelchair electronics. These switch-driving systems require the use of specialized control interfaces, special wheelchair electronics and special rehab wheelchairs all of which are very expensive and limit the use of switch driving control to a very limited number of high end wheelchairs. For individuals with severe progressive conditions, such as the ones indicated before, this means being able to drive their wheelchairs with a regular joystick at one point in time and then having to abandon the chair they are used to, in order to acquire a new chair (which may easily cost three to four times as much as their original chair) so that the needed electronics and driving interfaces can be purchased and incorporated to it.
Thus, what is needed is a universal single actuator-driving system for power wheelchairs, which can be attached to any wheelchair joystick and controlled by any of the single switches available for persons with disabilities.